Swapping a 4.0L v6 into a MII

You'll probably want to contact 51degII over at the mustangii.net site. He's been piecing a 4.0 swap together and working out the wiring splices. If you aren't a member there, message me your email and I'll pass it along to him for ya...

I think that the 4.0 V6 swap is a great idea for a MII!

The 4.0L OHV 5-speed in my 1991 Ranger has lots of power and has over 160K miles. I had to install a limited slip rear just so my Ranger was drivable in wet weather. The later 4.0L OHC engines have more power, but also have more complexity.

If you need any measurements, let me know. I've already checked the Ranger vs. MII frame rails and they are the same at 24" apart. Of course the Ranger engine sits a little higher.

The rear sump Ranger 4.0L oil pan might work fine also, but I haven't measured to be sure yet. The shorter engine (vs a 2.3L or 302) could mean that either the lower pulley or the small front of the 4.0L oilpan ends up over the suspension crossmember which would lead to a nice low engine placement. The MII rear 'toilet seat' brace might need to be notched for the rear sump though.

If the Ranger ECU is EEC IV, then the connections should be pretty much the same as the 5.0L EFI engine, so the popular 5.0L EEC IV wiring book could be useful. It should only require about 5 wires actually be connected to work.

If the OHC ECU is different, I would consider dropping back to the OHV engine. It has significant possibilities with a cam, headers, intake and head work.

I've seen pics of an early (German) Capri with the 4.0L OHC cam covers sticking through the hood, so its a tall engine. They should not be too tall for an MII, but I would measure before purchasing.

Hurst has a shifter for the Mazda 5-speed that all of the Rangers use that should cure some of the 'truck' shifter feel. The Hurst shifter has the same bolt-on shifter arrangement that the T-5 has, so you could probably use short T-5 handles with it. The factory shifter has an odd shifter attachment bolt that would not allow aftermarket handles.

The 5-speed in my 4.0L Ranger does not have the super low gearing (even with a 3.27 rear ratio) that you would expect from a truck trans. I think it would work fine in a MII.

Probably saw the pics of my freind's '74 Capri with the SOHC 4.0L. He used a 4.0L from a '97 Explorer so it still had a throttle cable. The wiring seemed like the easy part compared to fabbing motor mounts. The engine sits really high due to the oil pan clearance, and he only has about 1/4" between the driver's side valve cover and the power brake booster. The passenger side has about the same amount of clearance for the serpentine belt (but that's with the accessory layout for the Explorer). I seem to remember the wiring harness being pretty self contained so he only needed to figure out power, ground, key on, start, and guages. He was able to use a Mustang II V6 bellhousing and T-5 in the Capri and I believe the pilot bearing went in the flywheel instead of the crank so the T-5 properly reached the pilot bearing.

In a Capri, the engine is near ridiculous, tons of power at any rpm... but the car only weighs around 2600lb with a 200lb driver in it.

But the 5speed in the ranger the shifter sits more foward than with a T5 doesn't it?

Ah, I didn't think about shifter placement on the Mazda M5OD trans. I'll get under my Ranger in the next week or so and measure.